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  <div class="section" id="numpy-matrix-getfield">
<h1>numpy.matrix.getfield<a class="headerlink" href="#numpy-matrix-getfield" title="Permalink to this headline">¶</a></h1>
<p>method</p>
<dl class="method">
<dt id="numpy.matrix.getfield">
<code class="sig-prename descclassname">matrix.</code><code class="sig-name descname">getfield</code><span class="sig-paren">(</span><em class="sig-param">dtype</em>, <em class="sig-param">offset=0</em><span class="sig-paren">)</span><a class="headerlink" href="#numpy.matrix.getfield" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns a field of the given array as a certain type.</p>
<p>A field is a view of the array data with a given data-type. The values in
the view are determined by the given type and the offset into the current
array in bytes. The offset needs to be such that the view dtype fits in the
array dtype; for example an array of dtype complex128 has 16-byte elements.
If taking a view with a 32-bit integer (4 bytes), the offset needs to be
between 0 and 12 bytes.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl class="simple">
<dt><strong>dtype</strong><span class="classifier">str or dtype</span></dt><dd><p>The data type of the view. The dtype size of the view can not be larger
than that of the array itself.</p>
</dd>
<dt><strong>offset</strong><span class="classifier">int</span></dt><dd><p>Number of bytes to skip before beginning the element view.</p>
</dd>
</dl>
</dd>
</dl>
<p class="rubric">Examples</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">x</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">diag</span><span class="p">([</span><span class="mf">1.</span><span class="o">+</span><span class="mf">1.</span><span class="n">j</span><span class="p">]</span><span class="o">*</span><span class="mi">2</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="p">[</span><span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">]</span> <span class="o">=</span> <span class="mi">2</span> <span class="o">+</span> <span class="mf">4.</span><span class="n">j</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span>
<span class="go">array([[1.+1.j,  0.+0.j],</span>
<span class="go">       [0.+0.j,  2.+4.j]])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="o">.</span><span class="n">getfield</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">float64</span><span class="p">)</span>
<span class="go">array([[1.,  0.],</span>
<span class="go">       [0.,  2.]])</span>
</pre></div>
</div>
<p>By choosing an offset of 8 bytes we can select the complex part of the
array for our view:</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">x</span><span class="o">.</span><span class="n">getfield</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">float64</span><span class="p">,</span> <span class="n">offset</span><span class="o">=</span><span class="mi">8</span><span class="p">)</span>
<span class="go">array([[1.,  0.],</span>
<span class="go">       [0.,  4.]])</span>
</pre></div>
</div>
</dd></dl>

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